This maybe her normal heart rate.
You may notice now because you have not checked it before this.
Most people have a heart rate between 60-90/ min.
Some people have it between 50-- 60/ min and have no symptoms.
Most people below 50/min have complaints:
light-headness, dizziness, chest dicomfort during exercise, history of fainting.
Covid patients with severe infection who had previously normal heart rate have been found to have low heart rate after recovery.
This is because the S. A node(pacemaker) of heart is affected.
Next Steps
if she has no heart related symptoms, monitor saturation thrice a day with heart rate and document it.
continue medications for covid.
After her 15 day recovery from covid, seek a cardiologist advice with ECG.